Looks interesting, but I get the feeling using something like ScreenHero would work better. I've used ScreenHero for sort-of pair programming and it works extremely well + it's not limited to editors.
1. Both users are confined to looking at the same thing. 2. Only one user can input at a time. 3. One person may be stuck in an unfamiliar IDE. 4. Only 2? people can work on a thing.
We started to build Floobits after pair programming for 8 months or so because nothing else worked. Floobits also has a web based editor and basic support for terminal sharing. We also get to do really neat things because our protocol understands changes in source code; for instance, Floobits is self hosting and streams our changes to staging in hard real time. You can imagine other integration around source control, continuous deployment/integration too.
I think ScreenHero has its uses, but pair programming isn't its strongest.
But with a lightweight protocol like ssh with tmux/vim things feel much more responsive.
The responsiveness is the problem I assume they're trying to address with the individual editor plugins..
I described a similar solution to remote pair programming about a year ago : https://gist.github.com/aantix/1999816